Expanding piston.



Patented Dec. I0, |90I.

\ W. W. GREEN.

EXPANDING PISTN.

(Application filed Sept. 11, 1901.) (No Model.)

.f Y 'Y i@ UNITED STATES ATENfr Enron.

WILLIAM w. GREEN, on CHESTER., PENNSYLVANIA.

EXPANDING: PISTON.

SPECIFICATION forming part of Letters Patent No. 688,635, dated December10, 1901. Application iiled September 1l, 1901l Serial No. 75,040. (Nomodell) To @ZZ whom it may concern.-

Be it known that LWILLIAM W. GEEEN, a citizen of the United States,residing in Chester, in the county of Delaware, State of Pennsylvania,have invented certain Improvements in Expanding Pistons, of which thefollowing is a specification.

My invention relates to certain improvements in that form of piston forpumps, steam-engine cylinders, and the like having self-contained meansfor expanding the annular packing carried by the same, so that a tightor working iit may always be maintained in the cylinder.

My invention is fully illustrated in the accompanying drawings, inwhich- Figure l is a sectional view of an ordinary pump-cylinder with apiston arranged therein having the improved expanding means forming thesubject of my invention. Fig. 2 is a sectional View of the cylinder andpistonrod, taken on the line a a, Fig. 1, with one of the piston-platesremoved to show the means for expanding the packing. Fig. 3 is asectional view of said piston, taken on the line b b, Fig. 2; and Fig.at is a perspective view of one of the expanding segments.

The object of my invention is to provide the piston with expanding meansof such a character that the packing may be set up whenever necessary ordesirable without dismantling the piston and when set up may bevpositively held in the adjusted position without danger of workingloose. At the same time such expanding means may be positively retractedwhen one packing has been worn out and it is necessary to entirely renewthe same.

The packing l, which is preferably of some fibrous material plaited ortwisted in the form of a rope, is held between the flange 2 andremovable plate 3 of the piston. The flange 2 is provided with a centralsleeve ,1, having a tapered opening 5, to which the tapered end of thepiston-rod 6 is adapted, such rod being held in place by means ofsuitable nuts 7 and 8.. Carried by the piston between the flange 2 andplate 3 are a series of flan ged segments 9, adapted to be moved fromand toward the piston-rod 6. The sleeve 4; is apertured at 10,`and eachof said segments is `provided with a portion 11, entering said appartsare in operative engagement, and by p turning the collar 12 by anysuitable means the segments 9 may be moved from and toward thepiston-rod. To retain this collar in place and prevent any rise of thesame when turning, I provide a set-screw 17, passing through the collarand engaging a groove 1S, formed on the exterior of the central sleeve4.

Various means may be employed for turning the collar 1250 as to movetheflanged segments from and toward the piston-rod, and one form of suchmeans I have illustrated. Carried by said collar 12 are a series of lugs19, adapted to recesses20 in the plate 3 of the piston. This plate isprovided with the engaging portion 21, and when it is desired to expandthe packing to make a tighter lit against the walls of the cylinder aSpanner-wrench may be put over the nuts 7 and 8 to engage the portion21, whereby the piston-plate 3 may be given' a partial turn in thedirection of the arrow, Fig. 2. This will cause radial movement of theflanged segments 9 and the consequent expansion of the packing. The nuts7 and 8 may then be set up by any suitable means to hold the plate 3 inthe newly-adj usted position.- l

The cams 13, carried by the sleeve or collar 12, are provided with agradual curve, so that when said sleeve 12 is turned and the plate 3locked to the piston by the nuts 7 and 8 there will be sucientfrietional contact between the parts to maintain them positively in theexpanded position.

Having thus described my invention, I claim and desire to secure byLetters Patent-- l. The combination in a piston of the characterdescribed, of the ilange carried by the same, a movable plate, packingheld between said plate and flange, a sleeve carried by the ilange, aseries of hanged segments radially movable within said sleeve, a collarcarried by the sleeve, means for moving said collar,-

Ide

and means carried by said Collar and coacting with the iiangedk segmentsfor moving the 4 latter radially to expand the packing, substantially asdescribed.

2. The combination in apiston of the character described, ofthe ange, amovable plate, packing held between said flange and plate, a sleevecarried by said flange and adapted to fit over the end of thepiston-rod, said sleeve having a series of radial openings, a seriesol.' flanged segments radially movable with respect to the piston-rodand having portions `adapted to the apertures in the sleeve, lugs 4having a series of radial openings, a series ot' flanged segmentsradially movable with respect to the piston-rod and having portionsadapted to the apertures in the sleeve, lugs formed on said portions, acollarcarried by said sleeve, flanged cams carried by said collar andadapted to engage the lugs of the flanged segments, and means for movingsaid collar whereby the flanged segments may be given a radial movement.

4. The combination in a piston of the character described, ofthe iiange,a movable plate, packing held between said Iiange and plate, a sleevehaving a series of radial openings carried by the ilange, a seriesofiianged segments arranged between the flange and plate of the piston andhaving portionsadapted to the openings in the sleeve, a collar carriedby said sleeve, cams carried by said collar and serving to engage thesegments whereby they may be given radial movement, and lugs carried bythe end of said collar and adapted to engage recesses in the movableplate whereby a partial rotation of said plate will serve to move thesleeve andthereby impart radial movement Vto the iianged segments.

In testimony whereof I have signed my name to this specification in thepresence of two subscribing witnesses.

' WILLIAM NV. GREEN.

Witnesses:

DAVID F. ROSE, E. GARRETT.

